Authors compared the efficacy and safety of valdoxan in the treatment of depression in 22 patients with recurrent depressive disorder (RD) and 23 patients with bipolar affective disorder (BAD). Valdoxan was used on the night in dosage 25-50 mg during 8 weeks. Efficacy was assessed with psychometric scales HAM-D-17, CGI-S, CGI-I and visual analogous scales for falling asleep, night sleep quality, morning status and day activity. The antidepressant effect of the drug and the normalization of circadian rhythms were seen in the first week of treatment. To the end of treatment, there were 90.9% responders in the group with BAD and 91.3% in patients with RD. Percentages of patients with remission were 65.2% and 54.5%, respectively. It has been concluded that valdoxan does not cause unwanted side-effects as well as the risk of the inversion of a phase and/or the development of transitory hypomania in BAD.